Vibration damping equipment or apparatus takes on a number of forms, shapes, and sizes. Large industrial equipment, such as computer numerically controlled (CNC) machining or fabricating operations may be mounted on isolation platforms supported by gas filled bladders mounted between the platform and the bottom of a pit constructed in a factory. Such an isolation platform acts to protect sensitive equipment from vibrations emanating from adjacent machinery in the factory, or from outside sources such as heavy vehicles running on nearby roads and the like. Air bladders are ineffective in isolating consumer and commercial electronic because the high velocity of wave forms in the audible spectrum cause in the air bladder adiabatic compression which retain mechanical energy and passes vibration to the electronic component.
On a different size level, electronic equipment for both home use and for commercial use in recording studios in audio and visual recording, in television and radio studios and computer and other electronic facilities can benefit from being mounted on vibration isolation platforms. It is useful, and often necessary to provide vibration damping apparatus in order to provide high quality generation transmission and reception of electronic signals.
One such isolation platform is found in U.S. Pat. No. 5,197,707. This platform includes an open top rectangular box having a granular medium positioned therein with a plinth or top plate floating on the granular medium to isolate vibrations. The problems associated with not having the granular medium fully enclosed would allow such granules to escape.
A selectively tuned vibration absorber is shown in U.S. Pat. No. 6,279,679. In operation, a pair of these vibration absorbers are adapted to be mounted in spaced position on a plate that is affixed at its center to the back of a loudspeaker. Each apparatus includes a plurality of plates with small end spacers positioned between the plates at the opposing ends along the opposing end edges thereof. This apparatus is sized to be tuned to resonate at the fundamental resonance frequency of the low frequency loudspeaker. As such, it does not absorb vibrations from outside the piece of electronic equipment.
Additionally, a viscoelastic damping system is shown in U.S. Pat. No. 5,240,221. This system also is made up of a plurality of plates stacked together and separated with spacers. It is also meant to be mounted on an enclosure panel of a loudspeaker to attenuate the vibrations of the panel that may interfere with the desired loudspeaker output. In this patent, there is no disclosure of means for isolating the bolt (4) from the mounting block of the damping system.
Further, the cabinets of electronic equipment include, at times, spring mounted mounting pads having rubber or other elastic material on their bottom to isolate electronic equipment positioned in the cabinetry from outside vibrations. Springs are ineffective for isolating consumer and commercial electronics because springs store energy and excess mechanical energy is transferred to the electronic component as vibration. These isolation materials are exposed to airborne vibrations. These airborne mechanical disturbances cause the isolation materials to vibrate the electronic component.
A need has developed for an improved vibration isolation and damping apparatus or platform that provides superior vibration damping capabilities for home, commercial and industrial electronic equipment.
Another object of the present invention is the provision of an improved vibration damping apparatus or platform having lighter weight and less vibrating mass than heretofore known vibration damping apparatus. Another object of the present inventions is an isolation apparatus that isolates the internal isolation system from airborne vibration through an external double wall encasement.
It is therefore an object of the present invention, generally stated, to provide an improved vibration damping apparatus or platform for home, commercial and industrial electronic equipment.
Another object of the present invention is the provision of an improved vibration isolation or damping platform that lowers the resonant frequency of the upper portion of the platform to provide superior vibration isolation for electronic equipment mounted on such plinth or platform. Another object of the present invention is the inclusion of horizontally placed intermediate plinths between multiple isolation layers of polymers which diffuse residual energy passing through the viscoelastic material outward acting to dissipate vibration before reaching the next level of polymers.